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"Oumuamua came from the direction of Vega, a bright star in the Lyra constellation. But even at 85,700 miles per hour, it took so long to reach our solar system that Vega wasn't in the same position 300,000 years ago." CNN.

However, there is information on the motions of stars from ESA's Gaia mission (4 min. youtube with description), so it should be possible to project the motion of Oumuamua back it time to see if it was near any stars. Has anyone done this?

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    $\begingroup$ The full results from Gaia will not be available for several years. However, something like this may be possible when the second data release comes out next year. $\endgroup$
    – ProfRob
    Nov 22 '17 at 1:48
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A recently released paper on arXiv (Bailer-Jones et al., AJ) has made use of the recently released GAIA-DR2 data set, and specifically the 7 million stars that have full 6D information, to try and find plausible home stars for 'Oumuamua. They found 4 potential systems of which the closest encounter was at 0.6 parsecs with the M2.5 dwarf HIP 3757 at a relative velocity of 24.7 km/s, 1 million years ago. However all of the encounter stars have quite high encounter velocities. A giant planet or a binary system could provide the needed velocity but none of the 4 systems are known to be binaries or to harbor planets. However 7 million stars with full information is still a pretty small fraction of the total, a situation which will improve with later data releases.

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  • $\begingroup$ At 25km/s it would be abotu 80-90 light years away 100 million years ago. If it's a billion years old, it would have travelled 80,000 light years, which is beyond the precision of Gaia... Gaia will measure stars at 80 light years away to a precision of 20%, according to the ESA facts list. wolframalpha.com/input/?i=26km%2Fs+*+1000000000+years and The likely result of the available data: google.com/maps/dir/… $\endgroup$ Apr 26 at 0:08

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